[Car basic knowledge]New technology of automotive electronics

carThe electronic, intelligent, and networking of modern automobiles is an important symbol of the development of modern automobiles. With the increasing requirements of consumers for automobile functions and performance, automobiles are gradually transforming from mechanical systems to electronic systems. At present, the global automotive electronics industry is facing a high-speed Opportunities for growth. In foreign countries, electronic systems have accounted for 30% of the total cost of an ordinary car, and the proportion is even higher in high-end cars. In China, the configuration of electronic devices in middle- and high-end cars has approached or reached the level of developed countries in the foreign automobile industry. However, there is still a big gap between my country's automotive electronics industry and foreign countries, and it is necessary to increase research investment. After two stages of development in automotive electronics technology, it is now in the third stage. The first stage of automotive electronic equipment mainly uses discrete electronic components to form an electronic controller, and the transition from discrete electronic component products to integrated circuit products; the second stage mainly uses integrated circuits and 8-bit microprocessors to develop independent automotive-specific controls System; The third stage began in the 1990s, and automotive electronic equipment was widely controlled by 16-bit or 32-bit microprocessors, and the control technology was developing in the direction of intelligence and networking. At this stage, many new technical research fields and research hotspots have emerged. This article briefly introduces several typical aspects. 1. Wire control technology (control by—wire) The various control systems of automobiles are developing in the direction of electronization and automation. In the next 5-10 years, traditional automobile mechanical control systems will become electrical systems connected to high-performance CPUs through high-speed fault-tolerant communication buses.If the car will use electricalmotorAnd electronic control signals to achieve steer by-wire, brake by-wire, throttle by-wire and suspension by-wire, etc., using these The wire control system will completely replace the hydraulic and mechanical control in the existing system. One of the new technologies is DBW adopted in the new generation of Accord V6 sedan. DBW is the English abbreviation for throttle by wire, and it can also be called electronically controlled throttle, that is, the engine's throttle is controlled electronically. The traditional accelerator control method is that the driver directly controls the opening and closing degree of the engine accelerator by the accelerator cable by stepping on the accelerator pedal, thereby determining acceleration or deceleration. The driver’s action and the accelerator action are linked by the mechanical action of the cable . DBW changed this mechanical connection to an electronic connection. The driver still controls the cable by pressing the accelerator pedal.But the cable is not directly connected to the accelerator, but connected to an accelerator pedal positionsensor,sensorThe position change of the cable is converted into electrical signals and sent to the brain ECU (Electronic Controller) of the car. The ECU processes the collected sensor signals and sends commands to the throttle actuator control module, which then sends commands to the throttle actuator control module. Send a signal to the throttle actuator to control the opening and closing degree of the throttle. That is to say, the driver's action and the accelerator's action are connected through the electrical signals of the electronic components. Although from the structural point of view, DBW is more complicated than the traditional throttle control method, but the throttle control is more accurate than the traditional method. The engine can accurately adjust the fuel-air mixture entering the cylinder according to the various driving information of the car to improve the engine's combustion status. Thereby greatly improving the power and economy of the car. There are many advantages of using wire control technology. For example, the use of wire control does not require brake fluid, which protects the ecology and reduces maintenance; light weight; high performance (fast braking response); minimum brake wear (towardtireMore uniform force); simpler and faster installation and testing (module structure); more stable electronic interface; no mechanical connection between partitions; simple layout can increase electronic control functions; consistent pedal characteristics; fewer components than hydraulic systems, etc. . Two, CAN network Since there is still no communication network that can meet all the cost and performance requirements of future automobiles, automobile OEM manufacturers will still adopt a variety of networking protocols (including CAN, LIN, MOST, 1394, etc.). With the increasing application of electronic control units in automobiles, data communication between on-board electronic devices has become more and more important. It is necessary to construct automobile on-board electronic network systems based on distributed control systems. The rapid exchange of large amounts of data, high reliability and low cost are requirements for automotive electronic network systems. In this network system, each processor runs independently to control and improve the performance of a certain aspect of the car, while providing data services when other processors need it. The composition of the car's internal network mainly relies on bus transmission technology.